Percutaneous renal procedures can be used for a variety of medical purposes, including removal of kidney stones that are too large or too complex to be removed by another method, to remove or treat urothelial cancer in the urinary collecting system, or to treat kidney obstruction. These percutaneous surgical techniques generally utilize radiographic imagining to determine the precise location for desired access to a kidney. Using a needle, a puncture is made through the back and underlying tissues into the kidney. Once the tract has been established, a “safety” wire typically is passed from outside the body, through the kidney, and down the ureter toward the bladder. The tract is then dilated with a balloon or a rigid dilator, and a percutaneous sheath is placed over the dilating device. The sheath provides a portal through which different instruments and scopes can be placed in order to complete the percutaneous renal procedure.